50-kilobar gasketed diamond anvil cell for single-crystal x-ray diffractometer use with the crystal structure of Sb up to 26 kilobars as a test problem

Abstract

A single‐crystal gasketed diamond anvil cell of a new design for use on a diffractometer is described. It has achieved hydrostatic pressures of 50 kilobars as determined from the ruby fluorescence shift. The design combines several advantages. Nearly half the area of the Ewald sphere is available without having to remount the crystal. For reflecting planes nearly parallel to the diamond anvil faces, all reflections in the angular range ∼4°⩽ϑ⩽85° can be observed. Alignment of the diamonds, as well as loading and alignment of the sample crystals, is very simple and quick. The diffractometer geometry allows accurate measurements of weak reflections as well as accurate determinations of the x‐ray absorption corrections for the cell. The materials of construction are nontoxic except for one diamond mount, a small beryllium cylinder situated so that it is never touched, scraped, or rubbed. As a test problem, the z parameter of antimony has been found to increase linearly from z=0.23357 at 1 bar to z =0.2380±0.0005 at 26 kilobars.